Microelectrical-mechanical systems (MEMS) devices have experienced impressive and steady growth as they have integrated into people's everyday lives. Since their conceptualization in the 1970's, they have progressed from laboratory curiosity to integration in high-end systems, and, more recently, to widespread application in popular consumer devices.
A number of factors have fueled the growth in demand for MEMS devices, ranging from gains in performance and functionality to new processes to lower the manufacturing cost for the devices, to fundamental changes in the technology and materials used in the device manufacturing. Since MEMS contain by definition some sort of mechanical function, they present special challenges to fabrication and packaging technologies. While fabrication technologies have largely kept pace with market demand, the enormous difficulties in packaging such devices have weighed down its progress, resulting in an inappropriate proportion of costs (for some devices up to 80%) being relegated to the packaging area.